Wrenches especially adapted for use on fire hydrants have been the subject of patents for many years. An example is detailed in U.S. Pat. No. 4,690,019, a simplified version of which is illustrated in FIG. 1.
The illustrated wrench 10 includes a head 12 and a handle 14. An end 16 of the handle is fashioned with helical threads 18 designed to mate with corresponding threads in a base end 20 of the head.
In use, a firefighter must unthread the handle 14 from the head 12 enough to accommodate the fire hydrant fixture (e.g. a five-sided bolt head) in an opening 22. Then the firefighter must thread the handle back into the head in order to grip the fixture in the opening 22 prior to turning. This is a time-consuming sequence of operations. While in many contexts "time is money," in case of fire, time can be a matter of life or death.
The inherently slow unthread/thread operation of prior art wrenches is not their only drawback. Another is the time that can be lost fumbling with a wrench that falls off a hydrant. Due to the urgency of time, the firefighter typically does not thread the handle into the head to tightly grip the hydrant fixture. Instead, the handle is loosely coupled to the fixture--tightened only enough to avoid the wrench head from idly spinning around the fixture when the firefighter applies rotating torque. When the firefighter lets go of the wrench, the loose coupling often permits the wrench to fall off the hydrant onto the ground.
In accordance with an illustrative embodiment of the present invention, the foregoin, drawbacks of the prior art are overcome.
According to one aspect of the invention, a fire hydrant wrench is provided with a "chatter thread" arrangement that allows the firefighter to avoid much, if not all, of the handle-turning required in the prior art to attach a wrench to a hydrant.
According to another aspect of the invention, a fire hydrant wrench is provided with a release trigger that permits the wrench to be quickly disengaged from a hydrant.
According to another aspect of the invention, a fire hydrant wrench is provided with reversible means (e.g. gripper teeth) tending to prevent even a loosely coupled wrench from falling off a fire hydrant.
The foregoing and other features and advantages of the present invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.